Dear All
We need to realease a measure next to a quarry where there are explosive to fracture the rock.
we need to measure the vibrations of blasting at our measurements
as we are only measuring wind, I wonder if you have a solution for seismic measurement. even if it takes another datalogger
You will certainly need a high speed logger.
For seismic I use 24bit logger reading accelerometers at 200Hz.
How many sensors will you be reading?
Dear Steve
Many thanks for your quick answer
I'm not blocked for use another datalogger.
do you have an exemple of material for use?
do you think i can use my actual captor(bought on campbell scientific) with this datalogger?
regards
We do have customers measuring vibrations and seismic signals with our loggers, as the mid-range loggers can measure at 100 (even 250) Hz continuously and over 1 kHz in bursts. The logger is normally sensitive enough for this type of measurement. Measuring wind at the same time would not normally be an issue.
In Europe we do not have much experience with selection of seismic sensors or accelormeters that you would need for this measurement. Maybe other users have recommendations.
Send me more details of what you have. Are you in France?
www.datageo.co.uk supply accelerometers.
I think something you could consider is using the CDM-VW300 or CDM-VW305 with some vibrating wire strain gages. (Geokon 4000 or similar) Those may be able to capture a vibration event, depending on what structural member you are monitoring (i.e if it is steel). The CDM device is paired with the CR3000 datalogger and can capture data at 100 Hz for small channel counts.
https://www.campbellsci.com/cdm-vw300-overview
You could also consider some accelerometers, which in
some cases can capture seismic events with comparable
outputs to geophones. (see meas-spec.com or pcb.com for example).
You would need one of our faster loggers (CR3000 or CR9000X)
and need to know what kind of frequency response you are trying to capture.
This chart is helpful not only for some geophone
options, but for understanding the main issues at hand when selecting a geophone (output voltage response, usually V/m/sec, and then desired frequencies of interest):
http://www.passcal.nmt.edu/content/instrumentation/sensors/sensor-comparison-chart
In some events, the voltage on a geophone may go as high as 10V, but probably not much past that except for extreme cases (very large earthquakes). It may be that 5V and less is what you get for your blast events (compatible with our datalogger).
Sercel geophones (Model L-4) have been used, as well as Kinemetrics brand.
I recommend you contact your local Campbell Scientific support office for exploring the options on this.